We give a concentration inequality for stochastic version of the facility location problem. show objective Cn=minF?[0,1]2?|F|+?x?Xminf?F??x?f? is concentrated in an interval length O(n1/6) and E[Cn]=?(n2/3) if input X consists i.i.d. uniform points unit square. Our main tool to use geometric quantity, previously used design approximation algorithms problem, analyze martingale process. Many our ...